I had my plugs and wires changed by a GM dealer on my 2012 Avalanche. I noticed that it runs rough compared to before. I took it back and they hooked it up to computer and showed me it was not missing. I trust the dealer as my sister works there, but curious as to what else it could be if it looks ok on computer? I notice it much more when i first crank engine. Ideas?
You must be logged in to reply to this topic.